Effect of Interphase Interaction within Zinc-Filled Composite Coating on the Potential of the Cathodic Protection of Steel / Istomina A. S.,Safronov A. P. // RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY A. - 2011. - V. 85, l. 12. - P. 2227-2232.

ISSN/EISSN:

0036-0244 / нет данных

Type:

Article

Abstract:

The potential of cathodic protection of steel with composite coatings based on polystyrene (PS) filled by highly dispersed powders of zinc (Zn) of different forms and dispersivities is investigated. The potential for all PS/Zn systems with a low content of filler is shown to be less than for pure metal; as some critical value (the percolation threshold) is reached, the negative values of potential increase abruptly and become higher in absolute value than the potential of pure metal. The threshold zinc contents are found to depend on the particle shape and rise from 9 to 30 vol\% upon transitioning from spear-shaped to spherical particles. The electrochemical protection properties of a composite coating are correlate with the enthalpy of mixing of filled composites. The enthalpy of mixing in regions of low filling is shown to be negative, indicating strong interphase interaction; that in regions of high filling is positive. The positive enthalpy of mixing corresponds to compositions that generate the potential of cathodic protection. It is found that an increase in the concentration range of positive values of a composition's enthalpy of mixing occurs symbatically with a decrease in the threshold concentration of metallic zinc within the composition. We conclude that cathodic protection by zinc-filled polymeric composites is due to weak interphase interaction that results in the aggregation of particles of metallic zinc within a polymeric matrix and the appearance of an infinite cluster. In the case of PS/Zn compositions, it is shown that the infinite cluster appears at enthalpies of mixing greater than 0.6 J/g of the composition.

Author keywords:

composites; polystyrene; percolation threshold; cathodic protection potential; thermodynamics ELECTRICAL-CONDUCTIVITY; NACL SOLUTION; PERCOLATION; BEHAVIOR; PAINTS

DOI:

10.1134/S0036024411120132

Web of Science ID:

ISI:000297925700031

Соавторы в МНС:

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Другие поля

Поле	Значение
Month	DEC
Publisher	MAIK NAUKA/INTERPERIODICA/SPRINGER
Address	233 SPRING ST, NEW YORK, NY 10013-1578 USA
Language	English
Keywords-Plus	ELECTRICAL-CONDUCTIVITY; NACL SOLUTION; PERCOLATION; BEHAVIOR; PAINTS
Research-Areas	Chemistry
Web-of-Science-Categories	Chemistry, Physical
Author-Email	aigul-1407@mail.ru
Funding-Acknowledgement	Russian Foundation for Basic Research {[}02-96015, 10-08-00538]; Ural Branch of the Russian Academy of Sciences
Funding-Text	This work was supported by the Federal target program ``Scientists and Science Teachers of an Innovative Russia,{''} Russian Foundation for Basic Research (project nos. 02-96015 and 10-08-00538), and the Program for supporting of Basic Research by the Ural Branch of the Russian Academy of Sciences.
Number-of-Cited-References	20
Usage-Count-Since-2013	2
Journal-ISO	Russ. J. Phys. Chem. A
Doc-Delivery-Number	860CQ